Car wheel



sept. 24, 1929. M W POWELL 1,729,295

CAR WHEEL i Original Filed June 18, 1924 2 Sheets-Sheet l M-ONVVFoWgLk M. w. POWELL C R WHE Sept. 24, 1929.

Patented Sept. 24, l'929` UNITED STATES MILTON' W.' POWELL, OF BALTIMORE, MARYLAND CAR WHEEL A Application led .Tune 18, 1924, Serial No. 720,749. Renewed August.'17, 1929.

The invention relates to railway car brakes and has as an object the provision of a brake which will act upon the wheel at a point other than the tread of the wheel. An additional object is the provision of a brake which will be more elicient than the brakes now in use by providing pressure upon a large proportion of the circumference of the drum to which it is applied. Y

An added obj ect of the invention is the provision of a brake having readily renewable friction elements.

An illustrative embodiment of the invention is shown in the accompanying drawings, in which' i Fig. 1 is an illustration from the inside of a car wheel with the axle shown in section and with the connecting rods broken away.

Fig. 2 is a plan view.

Fig. 3 is an exploded perspective view.

The car wheel shown is or may be of the usual form. A brake drum 11 is shown upon said wheel and is preferably cast intergral therewith. Removable surface elements 12- 13 are shown as applied to the drum member 11 and fastened thereto by keys 12HL and 13a and with the member 11 making up a complete brake drum 14. The details of the removable elements 12-13 are shown and claimed in an application filed by myselfof even date herewith, Serial Number 720,7 50, now Patent No. 1,604,852 dated October 26, 1926.

To applybraking friction to the drum 14 a brake band is shown comprising straps 15- 16. One end of strap 15 is shown with a projection 17 pivotally hung to a bracket 18 as at 19. The end of the strap 16 is shown pivoted at 20 to the end ofthe strap 15. The opposite end of the strap 16 is outwardly curved and provided with a pivot 21, which pivot is connected by a link 22 to a lever 23 by means of a pivot. 24. The end of the lever 23 is piv-` otally connected at 25 to the strap 15 at onel end, and at 26 to the brake rod 2"? at its other end. Pull upon the brake rod 27 will therefore pull the strap 15-16 toward the drum 14 with great force.

Friction is produced against the drum 14 by means of shoes 28, each formed upon the arc of a circle `to fit the surface of the drum and as shown, each being formed with a channel 29 in its outer surface in which the strap 15 may lie. To secure the shoes 28 to thestraps 15 and 16 each shoe is provided with a. projection 30 adapted to ass through an opening in the strap, the projection having an opening 31 through its end. A spring 32 may' be slipped through the opening 31in each projection 30. The ends of the springs are shown as provided with curved surfaces 33 adapted to seat in recesses 34 in the straps to retain the springs in place. To' remove the shoes 28 the spring 32 which secures it in place must be flexed until the surface 33v can slip over the ridge 35 adjacent the recess 34, when the spring may be slipped circumfertially and removed from the opening 31 in the projection 30. 70 As an added means to prevent circumferential movement of the shoes 28 upon the straps 15--16 each shoe is provided with recesses 36 adapted to itover projections 37 uponthe strap 15 or 16. Preferably two sets of recesses and projections are supplied upon each shoe element 28.

When the parts become worn either the surface elements 12-13 may be renewed, or one or all of the shoe elements 28 without requirlngthe application of an entire new car wheel to thel axle or, as is the usual practice, an entire new axle with two new wheels attached'. The brake band disclosed which completely surrounds the drum and applies pressure 85 through a plurality of surfaces about the surface of the drum, 1which surfaces together make upa large proportion of the circumference of the drum, provides a very efficient braking action. In -addition the strains on the brake drum are entirely self-contained so as to be more eiiicient than the usual form of brake upon/railway cars.

I claim as my invention:

A brake mechanism for car wheels, comprising in combination a car wheel, an axle therefor having cast integral thereon a brake drum, removable surface elements applied to said drum, a pivoted brake band comprising sections surrounding said drum, removable shoes Carried by the sectional brake band, operating levers to control themovement of said bands, and a removable means to 'secure said shoes to said bands and to hold said shoes 5 against lateral movements.y 4 Y v In testimony whereof he hereunto axes his signature.

' MILTON W. POWELL. 

